KR102037136B1 - Apparatus for processing waste Per-Fluoro-Compounds gas and quencher therefor - Google Patents

Abstract

The present invention relates to a waste fluorine gas treating apparatus for treating fluorinated gases such as SF6, CF4, and NF3 emitted from semiconductor and display manufacturing processes.
Waste fluorine gas treatment device
A pretreatment apparatus for removing fine dust and acid components contained in the fluorinated gas discharged from the semiconductor and display manufacturing process;
A combustion reactor for thermally decomposing fluorinated gas from which fine dust and acid components are removed through the pretreatment apparatus at a high temperature;
A rapid cooling device for rapidly cooling a temperature of the hot combustion gas discharged from the combustion reactor;
A post-treatment device for removing fluorinated substances contained in the cooled combustion gas discharged from the rapid cooling device; And
A preheater for preheating combustion air provided to the combustion reactor;
It includes.

Description

Apparatus for processing waste Per-Fluoro-Compounds gas and quencher therefor}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorinated gas treating apparatus for treating waste fluoride (Per-Fluoro-Compounds) gases such as SF ₆ , CF ₄ , and NF ₃ emitted from semiconductor and display manufacturing processes. Pyrolysis method to increase processing efficiency

It relates to a waste fluorine gas treatment device and a rapid cooling device suitable therefor.

Fluorine gases, such as SF ₆ , CF ₄ , and NF ₃ , are used as cleaning gases in semiconductor and display processes. The product's productivity is improved by the cleaning ability of the fluorinated gas, and the amount of usage and emissions is steadily increasing.

Fluoride gas has a low reactivity with other gas components and does not decompose well, thereby reducing the loss rate of the product.

However, this fluoride gas is a greenhouse gas that accelerates global warming, and it shows a movement to reduce the use or convert to another material due to environmental issues at home and abroad.

On the other hand, semiconductors and display products are being used continuously because they are not easy to maintain the productivity and change of the existing production process, and as a result, there is a movement to reduce emissions.

Here are some ways to treat fluoride gases:

First, there are ways to recycle resources and reduce environmental pollution through separation recovery, which includes adsorption (PSA, TSA, Cryogenic) and membranes. However, this method has not received much attention because the fluorinated gas discharged is not composed of pure fluorine gas only. Specifically, since the fluoride gas discharged from the production process includes not only fluorine gas but also various substances, and also particles, the recovery method using a membrane or adsorption cannot properly exhibit its performance, and thus an actual industrial site. Is not being applied in.

Second, there is a treatment technology that decomposes or removes fluorinated gas and releases it into the atmosphere. Since this method is a proven technology in the industrial field unlike the separate recovery method, it has been predominant in the technology of treating fluorinated gas. Since fluoride gas is a very stabilized material, it is not immediately removed by any method other than reaction or combustion decomposition, and most of it is processed through two processes continuously. That is, it consists of the process of decomposing this fluoride gas, and the process of processing the acid and basic gas produced | generated by decomposition.

Third, there is a technology that lowers the decomposition activation energy so that it can be decomposed at a relatively low temperature, and only a few companies in the world, such as Hitachi and Korea Chemical Research Institute, possess it. Most of these technologies use catalysts to achieve this goal. The advantage is that high-temperature decomposition materials can be decomposed at relatively low temperatures (700 ° C). In the meantime, the durability of the catalyst at 700 ° C or higher has been a key factor in the development of this technology. In recent years, the technical level has been further improved by solving the durability problem of such a catalyst.

However, this technique also, as pointed out in the separation recovery technology, because the fluoride gas also contains other substances and particles, the sharp drop in catalyst activity is the biggest obstacle to the development of technology. Therefore, such technology has been developed into a process using a catalyst after a pretreatment process.

In the case of pyrolyzed fluorinated gas, rapid cooling of the cracked gas is essential because it may cause a problem in treating the decomposed material at high temperature if it is gradually cooled from high temperature to low temperature. To this end, in general, spraying water on a high-temperature cracked gas by cooling or spraying a steam generator, a combustion air preheating heat exchanger and a scrubber in a continuous manner recovers waste heat and simultaneously cools it from high temperature to low temperature. have.

However, all of the above methods are not effective for rapidly cooling from 1200-1350 ° C to below 100 ° C. Most of the time, the combination of two or more of the above methods, or when used alone, the cooled combustion gas is usually above 200 ° C.

[Patent Documents]

Patent Application Publication No. 10-2017-0037336 (published Apr. 4, 2017)

Patent Registration 10-151449 (2015.04.16. Registration)

The present invention has been invented in order to meet the above demands, and an object of the present invention is to provide a high-efficiency waste fluorine gas treating apparatus capable of treating fluorine gas discharged from a semiconductor and display manufacturing process with high efficiency.

Another object of the present invention is to provide a rapid cooling device suitable for the waste fluorine gas treatment device described above.

Waste fluoride gas treatment apparatus according to the present invention for achieving the above object is

In the waste fluoride gas treatment apparatus for treating waste fluoride gas discharged from the semiconductor, display manufacturing process,

A pretreatment device for removing fine dust and acid components contained in waste fluoride gas discharged from a semiconductor and display manufacturing process;

A combustion reactor for thermally decomposing fluorinated gas from which fine dust and acid components are removed through the pretreatment apparatus at a high temperature;

A rapid cooling device for rapidly cooling a temperature of the hot combustion gas discharged from the combustion reactor;

A post-treatment device for removing fluorinated substances contained in the cooled combustion gas discharged from the rapid cooling device; And

A preheater for preheating combustion air provided to the combustion reactor; It includes.

Here, the rapid cooling device

A rapid cooling tank for rapidly lowering the temperature of the combustion gas through heat exchange with water;

A downcoming pipe introducing the combustion gas discharged from the combustion reactor below a predetermined level of the rapid cooling tank;

A downcomer pedestal for supporting the downcomer;

An inner wall surrounding the downcomer at a predetermined distance;

Including;

Here, a plurality of gas outlets are drilled in the lower portion of the downcoming pipe along the circumferential direction of the downcoming pipe,

Inside the inner wall is characterized in that the water of a certain level is filled.

Here, the rapid cooling device

A cooling jacket coupled to the upper end of the downcomer and receiving water;

The upper end of the downcoming pipe is characterized in that a plurality of outlets through which the water received in the cooling jacket flows can be installed along the circumference of the downcoming pipe.

Here, the upper portion of the downcomer is characterized in that the taping in the shape of a funnel.

Here, the cooling jacket further comprises an emergency water supply tank for supplying water to the cooling jacket to receive a predetermined amount of water.

Here, the rapid cooling device

A circulating water pump for self-circulating water in the rapid cooling tank; And

A circulation water cooler installed in the circulation water pipe; It characterized in that it further comprises.

Here, the combustion reactor

A combustion chamber comprising a main burner for burning fuel; And

A reaction chamber surrounded by a refractory and providing an internal space for pyrolysis of the fluorinated gas at a high temperature;

Here, the main burner

A fuel injection rod for injecting fuel mixed with waste fluorine gas;

An injection hole surrounding the fuel injection rod in a funnel shape; And

Combustion air inlet for injecting combustion air tangentially with respect to the inner circumferential surface of the injection hole; It characterized in that to generate a vortex-like flame, including.

Here, the point a and the line perpendicular to the fuel injection rod at the combustion gas injection port meets the fuel injection rod is a point and the tip of the fuel injection rod is a point b, point a and b in the fuel injection rod The angle between the lines drawn on each of the points is characterized in that 50 to 70 degrees.

Here, the combustion gas injection port is characterized in that a plurality provided along the circumference of the injection port.

Rapid cooling device according to the present invention to achieve the above another object is to be used in the waste pyrolysis gas treatment device of the pyrolysis method,

A rapid cooling tank for rapidly lowering the temperature of the combustion gas through heat exchange with water;

A downcoming pipe introducing combustion gas below a predetermined level of the rapid cooling tank;

A downcomer pedestal for supporting the downcomer;

An inner wall surrounding the downcomer at a predetermined distance;

Including;

Here, a plurality of gas outlets are drilled in the lower portion of the downcoming pipe along the circumferential direction of the downcoming pipe,

Inside the inner wall is characterized in that the water of a certain level is filled.

Here, the rapid cooling device

A cooling jacket coupled to the upper end of the downcomer and receiving water;

The upper end of the downcoming pipe is characterized in that a plurality of outlets through which the water received in the cooling jacket flows can be installed along the circumference of the downcoming pipe.

Here, the upper portion of the downcomer is characterized in that the taping in the shape of a funnel.

The present invention is a device for maintaining the removal efficiency of 95% or more with respect to fluorinated gases such as SF ₆ , CF ₄ , NF ₃ , SF ₆ 1150 ~ 1300 ℃, CF ₄ 1100 ~ 1250 ℃, NF ₃ 950 ~ At a reaction temperature of 1100 ° C, the removal efficiency is higher than 95% for the high concentration, ie, the inlet concentration of each component of 1500-3000 ppm.

1 shows a configuration of a waste fluorine gas treatment apparatus according to the present invention.
FIG. 2 shows the configuration of the pretreatment apparatus shown in FIG. 1.
3 shows the configuration of the combustion chamber.
4 shows the configuration of the main burner.
5 shows the configuration of the reactor body.
6 is a cross-sectional view showing the configuration of a rapid cooling device.
7 shows the internal structure of the rapid cooling apparatus in detail.

Hereinafter, with reference to the accompanying drawings will be described in detail the configuration and operation of the present invention.

1 shows a configuration of a waste fluorine gas treatment apparatus according to the present invention.

Referring to FIG. 1, the waste fluorinated gas treating apparatus 100 according to the present invention includes a pretreatment device 102, a combustion reactor 104, a rapid cooling device (Quencher 106), a post-treatment device 108, and a preheater 110. It shows the overall configuration for the device of the present invention, including).

The pretreatment device 102 is for removing fine dust and acid contained in the fluorine gas discharged from the semiconductor, display manufacturing process, it is implemented as a wet electrostatic precipitator.

Fluoride gas is used for purge function in processes such as deposition and etching in semiconductor and display production processes. As a result, the fluorinated gas contains foreign substances (fine dust) and acid components attached to the product and is discharged. These materials adversely affect operation and management by causing clogging of the waste fluorinated gas treating apparatus 100 or by accelerating mechanical corrosion, causing frequent breakdown of equipment or an increase in maintenance costs.

To treat this, the pretreatment device 102 is used to remove the fine dust and acid contained in the fluoride gas.

In general, the method of removing impurities from the combustion cracking gas is a spray method or a scrubber (US Patent No. 5955037/5716428/5649985). This is the method by which hot cracked gas is injected into the lower part of the scrubber and passes through the scrubber and comes into contact with water coming down from the upper part of the scrubber so that the temperature of the cracked gas is cooled and impurities are diffused into the water so that the impurity free gas is discharged to the upper part of the scrubber. That's the basic way.

In the waste fluorinated gas treating apparatus 100 according to the present invention, the pretreatment device 102 is implemented as a wet electrostatic precipitator. The wet electrostatic precipitator is a method of charging the particles in the gas through high voltage discharge to thereby aggregate and remove fine dust and contaminants.

FIG. 2 shows the configuration of the pretreatment apparatus shown in FIG. 1.

Referring to FIG. 2, the pretreatment device 102 includes a wet electrostatic precipitator, and includes a particle removal device 202, a first ionizer 204, a first injection device 206, and a second ionizer ( 208, a second injection device 210 and a demister 212.

When a large amount of fine dust is introduced at once, the primary ionizer 204 may be overloaded to reduce dust collection efficiency. The fine particle removing device 202 first removes particles having a relatively large size from the fine dust to prevent the ionizer from lowering the charge efficiency of the ionizer generated by the fine particles acting as a non-resistance material in the primary ionizer 204. 204) to reduce the load. Water is sprayed into a fog nozzle to agglomerate and drop fine dust.

The first ionizer 204 generates a high pressure corona discharge to charge the fine particles mixed in the gas, and the charged fine particles are bonded to each other and attached to the dust collecting plate 204a. Particulates attached to the dust collecting plate 204a flow down through the water film formed on the dust collecting plate 204a and settle to the bottom.

The first injector 206 serves to remove an acid component in the gas. The acid component is dissolved through gas-liquid contact in the packing, and the dissolved acid is removed by neutralization with the caustic soda drug. Caustic soda is introduced into the tank according to the pH and sprayed through the nozzle.

The second ionizer 208 and the second spraying device 210 further increase the efficiency by further removing contaminants that have not been removed before.

The demister 212 is a device that traps water molecules so as not to be discharged to the outside. It mainly uses chevron type to drop water droplets by inertia collision.

In FIG. 2, HVPW stands for High Voltage Power Supply and stands for High Voltage Supply. This serves as the source of the electrostatic precipitating function.

The preheater 110 is for preheating combustion air provided to the combustion reactor 104.

The fuel is used to raise the reaction temperature of the combustion reactor 104. In order to reduce fuel consumption, a preheater 110 is constructed to raise the temperature of the combustion air. The preheater 110 is configured as an electric heater to control and maintain the desired temperature through electricity.

Preheating to about 300 ~ 400 ℃ can save 30 ~ 40% of fuel. When the preheating temperature is raised to 400 ° C. or higher, the operating conditions in the combustion reactor 104 are not stabilized and the flame disappears, or the operation balance is suddenly changed, so that stable operation is difficult. This is because the fuel input is reduced below the minimum fuel consumption of the designed burner, making it difficult to operate the burner normally. Therefore, it is important to manage the preheating temperature within the range of 300 ~ 400 ℃ to save fuel and ensure the stable operation of the equipment.

The combustion reactor 104 is pyrolyzed by heating the fluorinated gas from which fine dust and acid components have been removed through the pretreatment device 102.

The combustion reactor 104 serves to thermally decompose SF ₆ , CF ₄ , NF ₃ and the like by increasing SF ₆ to 1150 to 1300 ° C., CF ₄ to 1100 to 1250 ° C., and NF ₃ to 950 to 1100 ° C., respectively.

Combustion reactor 104 is composed of a combustion chamber 302 and the reactor body 304, the combustion chamber 302 is composed of a main burner 302a, an auxiliary burner 302b, and a flame detector 302c (FIG. 3). The reactor body 304 is composed of a refractory 304a, a thermometer 304b, an inspection window 304c, and the like (see FIG. 5).

Pyrolysis uses the principle of chemically decomposing molecules at a certain temperature. The decomposition temperature and calorie value are determined for each molecule. Waste fluorine gas treatment apparatus 100 of the present invention was configured to confirm the decomposition temperature for each fluorine gas and to maintain the reaction temperature through the burner.

Each molecule breaks down into atoms, and if not quenched through the quenching device 106, some atoms recombine again and are brought back to their original state. Alternatively, by-products are produced by secondary reaction with oxygen or other substances. This requires the rapid cooling device 106. Each decomposition atom is combined with water to exist as an acid component including hydrofluoric acid. This requires the post-processing device 108.

Ignition and temperature maintenance take place in the combustion chamber 302. Combustion chamber 302 is characterized in that to generate a flame of a short length, the short flame has the effect of reducing the size of the reactor body 304, the fuel consumption. In the present invention, it is configured to generate a vortex type spark by injecting combustion air in the vortex form. Vortex type sparks are shorter in length than straight type sparks having the same heating capacity, thereby helping to reduce the size of reactor body 304.

Referring to FIG. 3, the combustion chamber 302 includes a main burner 302a, an auxiliary burner 302b, a flame detector 302c, and a flame detection window 302d.

3 shows the configuration of the combustion chamber.

3, the main burner 302a, the auxiliary burner 302b, the flame detector 302c, and the flame detection window 302d for burning fuel are shown.

Meanwhile, referring to the left figure of FIG. 3, an auxiliary burner 302b, a flame detector 302c, and a flame detection window 302d are illustrated. In the left figure of FIG. 3, the main burner 302a has been omitted for the sake of clarity. In the left figure of FIG. 3, the main burner 302a is installed in a direction from the front to the front.

4 shows the configuration of the main burner.

Referring to FIG. 4, the main burner 302a includes a fuel injection rod 302a1, an injection hole 302a2, and a combustion air inlet 302a3.

The mixture of fuel and waste fluorine gas is injected through the fuel injection rod 302a1.

The injection hole 302a2 is for injecting combustion air, and the combustion air inlet 302a3 is configured to allow the combustion air to be injected in a vortex form.

Note in Fig. 4 is the combustion air inlet 302a3. Referring to FIG. 4A, a plurality of combustion air inlets 302a3 are provided along the inner circumferential surface of the injection hole 302a2, preferably eight. Referring to FIG. 4B, the combustion air inlet 302a3 is installed to inject combustion air in a tangential direction with respect to the inner circumferential surface of the injection hole 302a2.

Combustion air injected in the tangential direction along the inner circumferential surface of the injection hole 302a2 is injected while rotating along the inner circumferential surface of the injection hole 302a2. That is, the combustion air is injected in the form of vortex. Combustion air injected in the vortex form meets fuel at the tip of the fuel injection rod 302a1, and ignites it to generate a spark. The spark generated thereby becomes a vortex.

Referring to FIG. 4C, the combustion air is introduced into the tangential direction of the injection hole 302a2 from the combustion air inlet 302a3.

Referring to FIG. 4D, the point where the line drawn perpendicular to the fuel injection direction and the fuel injection rod 302a1 meets at the combustion air inlet 302a3 is point a, and the tip of the fuel injection rod 302a1 is b. In terms of points, it is preferable that the angles between the lines drawn at points a and b of the combustion air inlet 302a3 be 50 to 70 degrees.

Combustion air introduced through the combustion air inlet 302a3 is injected in a tangential direction with respect to the inner circumferential surface of the injection hole 302a2, and then rotates along the inner circumferential surface of the injection hole 302a2. . As a result, the spark generated in the combustion chamber 302 takes the form of a vortex.

The auxiliary burner 302b is used for initial ignition because the ignition device is configured inside, and the operation of the auxiliary burner 302b is stopped when the function is passed to the main burner 302a.

The reactor body 304 can be minimized due to the nature of the combustion chamber 302 generating a vortex-shaped flame. That is, since the same effect can be obtained even with a shorter length of flame than a conventional direct flame due to the vortex type spark generated in the combustion chamber 302, the length of the reactor body 304 can be minimized.

On the other hand, the thermometer was provided to control and interlock the reaction temperature in the reactor body 304 and the fuel supply of the combustion chamber 302 main burner 302a. It is desirable to preheat the combustion air to 300 to 400 degrees to save fuel usage.

When the preheating temperature is raised to 400 degrees or more, the fuel input amount of the main burner 302a is reduced to less than or equal to the minimum fuel amount, resulting in loss of flame or incomplete combustion. Therefore, it is preferable to operate while maintaining the preheating temperature in the range of 300 to 400 degrees.

5 shows the configuration of the reactor body.

5, the inner peripheral surface of the reactor main body 304 is surrounded by the refractory 304a, and the thermometer 304b and the inspection window 304c are provided.

A quencher 106 rapidly cools the combustion gas discharged from the combustion reactor 104.

When the temperature of the very high combustion gas drops slowly, not rapidly, at 950-1300 ° C, recombination of the fluoride gas is primarily performed. In this case, the removal efficiency is lowered by 5% to 20%. In addition, dioxin is generated secondarily, or by-products, or other forms of pollutants. Therefore, it is necessary to cool the hot combustion gas rapidly.

6 is a cross-sectional view showing the configuration of a rapid cooling device.

Quenchers 106 are located inside the rapid cooling tank 502, the circulating water pump 504, the circulating water cooler 506, the emergency water supply tank 508 (see FIG. 1), and the rapid cooling tank as follows. The down pipe 510 and the inner wall 512 surrounding the central portion of the down pipe 510, the cooling jacket 514, the down pipe stand 516 and the like. The rapid cooling device shown in FIG. 5 corresponds to the rapid cooling device in the summary of the present invention.

The rapid cooling tank 502 rapidly lowers the temperature of the combustion gas through direct heat exchange with water.

The rapid cooling tank 502 maintains a state filled with water up to a certain level (about 70% based on the entire length of the inner wall), and is a basic device in which rapid cooling is performed. The circulating water pump 504 serves to self circulate the water inside the rapid cooling tank 502. The water filled in the rapid cooling tank 502 takes heat of the combustion gas of a high temperature, and the water temperature inside the rapid cooling tank 502 rises to 70 degrees or more.

The temperature of the rapid cooling tank 502 must be maintained at 50 to 70 degrees so that the rapid cooling device 106 can function properly. Accordingly, the circulation water cooler 506 is installed in the circulation water pipe so as to maintain the water temperature of the rapid cooling device 106 within the range of 40 to 70 degrees. In the circulating water cooler 506, the water temperature is lowered through heat exchange with the coolant, thereby maintaining the normal operation of the rapid cooling device 106.

The rapid cooling device 106 functions to lower the temperature of the high combustion gas of 950 degrees or more in the range of 70 to 100 degrees within 1 to 2 seconds. At the heart of the rapid cooling function is the interaction of the rapid cooling tank 502 with the devices configured therein.

An inner wall 512 surrounding the downcomer 510, the downcomer 516, and the downcomer 510 is installed in the rapid cooling tank 502. The downcomer 510 is a passage through which the combustion gas from the reactor body 304 flows into the rapid cooling tank 502. The downcomer pedestal 516 is installed at the bottom of the rapid cooling tank 502 and supports the downcomer 510.

It is important to select the material of the downcomer 510 because the downcomer 510 may be deformed, cracked, and corroded by direct combustion gas of high temperature. The downcomer 510 is made of hastelloy, titanium-based metal or reinforced graphite.

Cooling jacket 514 is configured on the downcomer 510 to prevent deformation of the metal or graphite constituting the downcomer 510. The cooling jacket 514 is always filled with water, and a certain amount of the cooling jacket 514 is configured to flow down while forming a water film into the downcomer 510.

If there is not enough water in the cooling jacket 514 or the water supply is stopped, the entire rapid cooling device 106 may be damaged by the temperature rise due to the crack of the downcomer 510, so that the quantity of the cooling jacket 514 The emergency water supply tank 508 is configured to maintain the temperature, and the control system interlocks with the flow meter of the cooling jacket 514 supply pipe and the temperature in the rapid cooling tank 502 to maintain safety in an emergency.

The internal refractory 518 is also configured at the coupling portion between the upper portion of the cooling jacket 514 and the reactor body 304 to prevent direct heat from reaching the downcomer 510.

Inside the inner wall 512 where the downcomer 510 is located, about 20 to 30% of water is occupied based on the entire length of the inner wall 512, and the outer wall 512 is based on the entire length of the inner wall 512. About 70% of the water is filled.

The gas outlet 510c of the downcomer 510 is submerged in water, and is configured to push water out of the pressure of the combustion reactor so that the water flows along the inner wall 512 and overflows to the outside of the inner wall 512.

Before the waste fluorine gas treatment device 100 operates, the water level is the same inside and outside the inner wall 512, but when the waste fluorine gas treatment device 100 operates, the water level inside the inner wall 512 decreases due to the pressure of the gas. The actual differential pressure results in a pressure difference of 800 mmAq, which is assumed to be a difference of 800 mm between the inner and outer water levels.

A plurality of gas outlets 510c are formed in the lower portion of the downcomer 510 and the gas outlets 510c are directly in contact with the water of the rapid cooling tank 502 through the gas outlets 510c.

Under the downcomer 510 is a downcomer 516 is configured to fix the position of the downcomer 510. An inner wall 512 surrounding the lower portion of the downcomer 510 at regular intervals is installed, and the inner wall 512 plays a decisive function of rapid cooling.

7 shows the configuration inside the rapid cooling apparatus in detail.

A plurality of gas discharge ports 510c are formed at the lower end portion (between point D and point E in FIG. 6) of the downcomer 510. The plurality of gas outlets 510c are perforated along the circumference of the downcomer 510 at the end of the downcomer 510. The lower part of the downcomer 510 is supported by the downcomer pedestal 516, and the combustion gas is discharged into the water only through the gas outlet 510c.

The downcomer 510 is submerged in water. The high temperature combustion gas discharged from the combustion reactor 104 is discharged through the plurality of gas discharge ports 510c installed at the end of the downcomer 510 and is evenly spread in the water.

After maximizing contact with water in this process, the gas exiting the water surface is discharged through the outlet 502a installed on the upper portion of the rapid cooling tank 502. (The white arrow in Fig. 6 shows the flow of combustion gas.) The outlet 502a is preferably installed at a position higher than the water level of the water filled in the rapid cooling tank 502.

On the other hand, an inner wall 512 is formed around the lower end of the downcomer 510, and the inner wall 512 is formed to surround the downcomer 510 at a predetermined distance.

The gas from the downcomer 510 pushes the water inside the inner wall 512 of the rapid cooling tank 502 at its pressure, and the water thus pushed up into the inner wall 512 to move out of the inner wall 512. Will come down. Water inside the inner wall 512 flows outward of the inner wall 512 through a gap between the inner wall 512 and the upper portion of the downcomer 510.

Water and combustion gas rising up inside the inner wall 512 is primarily a direct heat exchange. More than 90% heat exchange occurs in this process.

The water in the rapid cooling tank 502 circulates through the inner wall 512 and drastically lowers the temperature of the combustion gas. When water is discharged from the inner wall 512 to the outside, there is no water inside the inner wall 512.

In this case, a certain amount of water is sent into the inner wall 512 through the circulation hole 512a outside the inner wall 512, and the cooling jacket 514 also supplies some water. (The black arrows inside the rapid cooling tank 502 in FIG. 7 show the flow of water inside the rapid cooling tank 502.)

In the present invention, when the material of the downcomer 510 is graphite-based, cracks may occur due to high temperature. Therefore, if a metal material such as Hastelloy is used, cracking does not occur.

When using a graphite-based material to form a water film flowing through the inner circumferential surface, it is minimized that the high temperature of the combustion gas directly affects the downcomer 510. In FIG. 6, the arrow shown inside the downcomer 510 shows the flow of water in the downcomer 510. As such, it is necessary to form a flow path in order to form a water film flowing on the inner circumferential surface of the downcomer 510. In the case of metal, of course, there is no need.

Referring to FIG. 7, a plurality of drain holes 510a are formed at a portion connected between the cooling jacket 514 (between A point and B point in FIG. 6, hereinafter referred to as the upper end of the downcomer). A plurality of drain holes 510a are perforated along the circumference of the downcomer 510.

Water contained in the cooling jacket 514 flows into the inner circumferential surface of the downcomer 510 through a plurality of drains 510a provided at an upper end of the downcomer 510. Water flowing into the inner circumferential surface of the downcomer 510 flows down the inner circumferential surface of the downcomer 510 due to gravity and forms a water film. This water film phenomenon causes less than 10% heat exchange. By the action of the water film and the inner wall, the temperature of the combustion gas is cooled and discharged within a desired range.

Taping of the downcomer 510 in a funnel shape at the lower portion of the cooling jacket 514 (between B and C in FIG. 6, hereinafter referred to as the upper part of the downcomer). As the water is lowered by the tapered portion 510b formed at the upper portion of the downcomer 510 as described above, the water film flowing along the inner circumferential surface of the downcomer 510 may be more naturally formed.

The aftertreatment device 108 removes fluorides (F, S, N, etc.) contained in the cooled combustion gas discharged from the rapid cooling device 106. The aftertreatment device 108 is implemented with a wet electrostatic precipitator.

The aftertreatment device 108 is constructed almost similarly to the pretreatment device 102. The difference is that the fine particle removal device 202 which eliminates fine dust reduces the load of the rear end device. Unlike the large amount of fine dust generated in the semiconductor display process, it was excluded because a large amount of refractories, dust, etc. precipitated in the rapid cooler, and the fine dust was introduced at a concentration sufficiently removable from the ionizer.

As shown in FIG. 1, the reason for separately configuring the stack is that if the present invention is applied to the CDM business or the domestic carbon credit market, it is necessary to configure the stack as a rule for analysis and measurement. It was.

The acid component is removed from the injector and the dust and the acid component adhered to the fine dust are removed together in the ionizer device to prevent contaminants from being released into the atmosphere.

When the fluorinated gas is decomposed, elements of fluoride (eg, F, S, N) are present. Element F encounters water and becomes HF, or hydrofluoric acid, which causes corrosion of the plant and leakage of pollutants to the outside. In addition, in the case of SF ₆ , S is released in the form of sulfuric acid, in the case of NF ₃ , N in the form of nitric acid may cause problems. The post-treatment device 108 was configured to remove this contaminant.

Although it can be treated by a general cleaning method, the concentration of contaminants in the process gas is very high. For example, in the case of SF ₆ , when the inlet concentration is 2,000 ppm, the sulfuric acid concentration is 2,000 ppm and the hydrofluoric acid concentration is 12,000 ppm. In the case of NF _3, when the concentration of incorporation is 2,000 ppm, the concentration of nitric acid is 2,000 ppm and the concentration of hydrofluoric acid is 6,000 ppm.

In this way, if the concentration of the treatment component is high, the size of the equipment increases, and several units must be installed for stable operation. Thus, the post-treatment device 108 is constructed at the rear end so as to remove not only high concentration treatment but also fine particles generated in the reactor. Use the same type of equipment as the pretreatment plant.

The terms or words used in this specification and claims are not to be construed as being limited to their ordinary or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best describe their invention. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention.

Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention, and do not represent all of the technical idea of the present invention, these can be replaced at the time of the present application It should be understood that there may be various equivalents and variations.

100 .... Waste Fluoride Gas Treatment System
102 Pretreatment Unit 104 Combustion Reactor
106 .... Quick Cooling Unit 108 ... Aftertreatment Unit
110 .... Preheater
202 ... particulate removal device 204 ... first ionizer
206 ... first injection device 208 ... second injection device
212 ... Demister
302.Combustion chamber
302a ... main burner 302b ... secondary burner
302c.Flame Detector 302d ... Flame Detector
304 ... reactor body
304a ... Refractory 304b ... Thermometer
304c ... inspection window
302a1 ... fuel injection rod 302a2 ... injection hole
302a3.Combustion air inlet
502 ... Quick Cooling Tank 502a ... Outlet
504 circulating water pump 506 circulating water cooler
508 ... emergency water supply tank 510 ...
510a ... drain 510b ... tape
512 ... inner wall 512a ... circulation hole
514 ... cooling jacket 516 ... downpipe stand
518,520 ... Refractory

Claims (12)

delete In the waste fluoride gas treatment apparatus for treating waste fluoride gas discharged from the semiconductor, display manufacturing process,
A pretreatment device for removing fine dust and acid components contained in waste fluoride gas discharged from a semiconductor and display manufacturing process;
A combustion reactor for thermally decomposing fluorinated gas from which fine dust and acid components are removed through the pretreatment apparatus at a high temperature;
A rapid cooling device for rapidly cooling a temperature of the hot combustion gas discharged from the combustion reactor;
The rapid cooling device includes a rapid cooling tank for rapidly lowering the temperature of the combustion gas through heat exchange with water;
A downcoming pipe introducing the combustion gas discharged from the combustion reactor below a predetermined level of the rapid cooling tank;
A downcomer pedestal for supporting the downcomer;
It includes; inner wall surrounding the down pipe at a certain distance;
Here, a plurality of gas outlets are drilled in the lower portion of the downcoming pipe along the circumferential direction of the downcoming pipe,
Inside the inner wall is filled with water of a certain level,
A post-treatment device for removing fluorinated substances contained in the cooled combustion gas discharged from the rapid cooling device; And
And a preheater for preheating combustion air provided to the combustion reactor. In the waste fluoride gas treatment apparatus for treating waste fluoride gas discharged from the semiconductor, display manufacturing process,
A pretreatment device for removing fine dust and acid components contained in waste fluoride gas discharged from a semiconductor and display manufacturing process;
A combustion reactor for thermally decomposing fluorinated gas from which fine dust and acid components are removed through the pretreatment apparatus at a high temperature;
A rapid cooling device for rapidly cooling a temperature of the hot combustion gas discharged from the combustion reactor;
The rapid cooling device includes a downcoming pipe for introducing the combustion gas discharged from the combustion reactor below a predetermined level of the rapid cooling tank;
A cooling jacket coupled to the upper end of the downcomer and receiving water;
At the upper end of the downcomer, a plurality of outlets through which water contained in the cooling jacket flows are installed along a circumference of the downcomer,
A post-treatment device for removing fluorinated substances contained in the cooled combustion gas discharged from the rapid cooling device; And
And a preheater for preheating combustion air provided to the combustion reactor. The apparatus of claim 3, wherein the upper portion of the downcomer is tapered in a funnel shape.
The method of claim 3,
And an emergency water supply tank for supplying water to the cooling jacket so that the cooling jacket receives a predetermined amount of water.
The method of claim 2, wherein the rapid cooling device
A circulating water pump for self-circulating water in the rapid cooling tank; And
A circulation water cooler installed in the circulation water pipe;
Waste fluoride gas treatment apparatus further comprising a.
In the waste fluoride gas treatment apparatus for treating waste fluoride gas discharged from the semiconductor, display manufacturing process,
A pretreatment device for removing fine dust and acid components contained in waste fluoride gas discharged from a semiconductor and display manufacturing process;
A combustion reactor for thermally decomposing fluorinated gas from which fine dust and acid components are removed through the pretreatment apparatus at a high temperature;
The combustion reactor includes a combustion chamber including a main burner for burning fuel; And
A reaction chamber surrounded by a refractory and providing an internal space for pyrolysis of the fluorinated gas at a high temperature;
Here, the main burner
A fuel injection rod for injecting fuel mixed with waste fluorine gas;
An injection hole surrounding the fuel injection rod in a funnel shape; And
Combustion air inlet for injecting combustion air tangentially with respect to the inner circumferential surface of the injection hole; Generates sparks in the form of vortex, including
A rapid cooling device for rapidly cooling a temperature of the hot combustion gas discharged from the combustion reactor;
A post-treatment device for removing fluorinated substances contained in the cooled combustion gas discharged from the rapid cooling device; And
And a preheater for preheating combustion air provided to the combustion reactor. The fuel injection rod according to claim 7, wherein a point perpendicular to the fuel injection rod at the combustion air inlet meets the fuel injection rod at point a and a tip of the fuel injection rod at point b is used. Waste angle fluorine gas treatment apparatus, characterized in that the angle between the lines drawn on each of the points a and b is 50 to 70 degrees. The waste fluorinated gas treating apparatus according to claim 8, wherein a plurality of the combustion air inlets are provided along a circumference of the inlet. In the rapid cooling device used in the waste pyrolysis gas treatment device of the pyrolysis method,
A rapid cooling tank for rapidly lowering the temperature of the combustion gas through heat exchange with water;
A downcoming pipe introducing combustion gas below a predetermined level of the rapid cooling tank;
A downcomer pedestal for supporting the downcomer;
An inner wall surrounding the downcomer at a predetermined distance;
Including;
Here, a plurality of gas outlets are drilled in the lower portion of the downcoming pipe along the circumferential direction of the downcoming pipe,
Rapid cooling device, characterized in that the inside of the inner wall is filled with water of a certain level.
The method of claim 10, wherein the rapid cooling device
A cooling jacket coupled to the upper end of the downcomer and receiving water;
The upper end of the downcomer is a rapid cooling apparatus, characterized in that a plurality of outlets through which the water contained in the cooling jacket flows is installed along the circumference of the downcomer.
12. The rapid cooling apparatus of claim 11, wherein an upper portion of the downcomer is tapered in a funnel shape.

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